The present invention relates to a computer system, and more particularly to a system status maintaining and supporting apparatus in which one console is commonly connected to a central processing unit (CPU) board and a system status maintenance and support processor (MSP) board. Moreover, this system status maintaining and supporting apparatus is capable of monitoring a system status in a remotely controlled section by the use of the input/output port of the MSP board without system bus utilization.
A common objective of system status maintaining and supporting apparatus is to let a user know what has happened in the computer system, by periodically supervising the power source or operating state of the computer system, thereby enabling a user to take the appropriate measures for computer system faults. The system status maintaining and supporting apparatus includes an MSP board, a monitor for the MSP board, a CPU board for controlling the whole computer system, and a console connected to the CPU board.
Here, the console is a cathode ray tube terminal used to check the system status or to manage different duties by the supervisor of the computer system. In addition to having a similar configuration as a general terminal, the console performs many specific functions resulting from the direct connection to the CPU. For the most part, it is placed adjacent to the main body of a computer.
FIG. 1 shows the hardware structure of a general computer system.
With the basic elements of a CPU, a memory device, and an input/output (I/O) device, the general computer system consists of an MSP board, a file I/O processor board, a small computer system interface (hereinafter referred to as an "SCSI") bus, a versa module Europe (VME) bus, an SCSI host adapter board acting as an interface between the SCSI bus and the VME bus, and so on, as shown in FIG. 1.
In such a computer system, there has been a necessity for the proposed standard of a common bus for interboard-connection in order to have moduled function that is the result of module division of a plurality of functions. A typical bus meeting international approval is the VME bus, wherein the term "versa" used in versa module Europe bus, designates the developed bus for Motorola's MC68000 processor. Also, the reference to "Europe" signifies that the board size for the VME bus follows the Eurocard format (the stipulated rules of IEC and DIN standards). Additionally, a VSB bus is the abbreviation for a VME-sub bus. The VSB bus utilization results in the removal of heavy traffic on the global bus and total throughput enhancement, i.e., it is employed in a local sub system, as a secondary bus.
The SCSI bus plays the role of interconnection between a peripheral device such as a hard disc controller HDC, a cartridge controller CTC and a magnetic tape driver MTD and the like, while an SCSI host adapter board acts as an interface between SCSI bus and the VME bus.
All functional boards except an interboard-connection bus include a CPU provided for controlling the overall system and arithmetic operation, a console connected to the CPU, a main memory device, a cache memory (not shown) which is a high speed memory (positioned between the CPU and the main memory device), an interface board connected to a printer and a modem, an MSP processor connected to a diagnostic terminal, a file I/O processor board, a memory device, a memory device controller, and an SCSI host adapter board functioning as an interface between the SCSI bus and the VME bus.
In order to let a user know what has happened in the computer system by periodically supervising the computer system's power source or operating status for the purpose of enhancing the computer system's reliability, the system status maintaining and supporting apparatus consists of an MSP board 40, a system status maintaining and supporting monitor 20 connected to MSP board 40, a CPU board 30 for controlling the whole computer system, and a console 10 connected to CPU board 30, as shown in FIG. 2A.
This configuration has given rise to such problems as higher cost and increased space, because two terminals are used for monitoring the system status.
As shown in FIG. 2B, another maintaining and supporting apparatus employs only one console to monitor the system. When a certain fault is sensed in MSP board 40, data to be output to console 10 is temporarily stored in a predetermined area of a memory device board 50 via the VME bus. Thereafter, CPU 30 recognizes an interrupt generation and in turn reads out the stored contents of memory device board 50, thereby displaying it on console 10. In order to precisely diagnose the computer system, a console port connected to CPU board 30 must be utilized by being moved to MSP board 40 when MSP board 40 is operating, and thus it is impossible to use CPU board 30. The use of one console causes CPU board 30 to process a lot of information whenever a certain fault occurs in the computer system, resulting in lowering the overall computer system's performance.
Consequently, the two above-mentioned apparatuses have a problem in which the VME bus 100 must be utilized to remotely monitor the computer system.